package com.zhou.unsafe;

import java.util.*;
import java.util.concurrent.CopyOnWriteArrayList;

public class ListTest {
    public static void main(String[] args) {

        /*
        并发下的List不安全
        解决方案:
            1.List<String> list = new Vector<>();
            2.List<String> list = Collections.synchronizedList(new ArrayList<>());
            3.List<String> list = new CopyOnWriteArrayList<>();
         */

        List<String> list = new CopyOnWriteArrayList<>();


        for (int i = 1; i <= 100; i++) {
            new Thread(()->{
                list.add(UUID.randomUUID().toString().substring(0, 5));
                System.out.println(list);
            }, String.valueOf(i)).start();
        }
    }
}
